The Laser Interferometer Gravitational wave Observatory (LIGO) made the first ever incident detection of gravitational waves on September 14, 2015, inaugurating gravitational wave astronomy as a new tool to explore the hidden universe of black holes and other exotic objects. With the second observing run of the Advanced LIGO detectors, alerts are coordinated with over 60 astronomy collaborations to search for an elusive multimessenger source, a signal that could be detected both in gravitational waves and electromagnetic radiation.